v1.5.0

Added

• Handle filtering tools and resources #85 @yjacquin
• Support for resource templates 🥳 Big thanks to @danielcooper for the contribution #84 co-authored by @danielcooper and @yjacquin
• Possibility to authorize requests before tool calls #79 @EuanEdgar
• Possibility to read request headers in tool calls #78 @EuanEdgar

Changed

• Bump Dependencies #86 @aothelal
• ⚠️ Resources are now stateless, meaning that in-memory resources won't work anymore, they require an external data source such as database, file to read and write too, etc. This was needed for a refactoring of the resource class for the resource template PR

Fixed

• Stop overriding log level to info #91 @yjacquin
• Properly handle ping request responses from clients #89 @yjacquin
• Add Thread Safety to RackTransport sse_clients #82 @Kevin-K

What's Changed

• Add configuration docs for Zed by @andyw8 in #76
• ✨ Expose headers to tools by @EuanEdgar in #78
• fix: undefined local variable or method "headers" by @k0va1 in #87
• Bump dependencies by @aothelal in #86
• Add thread safety to RackTransport sse_clients by @Kevin-K in #82
• ✨ Authorize requests before invoking tools by @EuanEdgar in #79
• Add Resource templates by @yjacquin in #84
• ✨ Add Filtering to tools and resources by @yjacquin in #85
• Properly handle ping request responses by @yjacquin in #89
• Stop overriding log level in server initialization by @yjacquin in #91
• Release v1.5.0 by @yjacquin in #92

New Contributors

• @andyw8 made their first contribution in #76
• @EuanEdgar made their first contribution in #78
• @k0va1 made their first contribution in #87
• @aothelal made their first contribution in #86
• @Kevin-K made their first contribution in #82

Full Changelog: v1.4.0...v1.5.0

v1.4.0

Added

• Conditionnally hidden properties for tool calls (#70) #70 @yjacquin
• Metadata to tool call results (#69) #69 @yjacquin
• Link to official Discord Server in README.md

What's Changed

• Add Metadata to Tool call results by @yjacquin in #69
• Support adding conditionnally hidden properties by @yjacquin in #70

Full Changelog: v1.3.2...v1.4.0

v1.3.2

Changed

• Logs are now less verbose by default #64 @yjacquin

Fixed

• Fix undefined method `call' for an instance of String error log #61 @radwo

What's Changed

• 🐛 change empty string to empty array by @radwo in #61
• 🤫 Make logs less noisy by @yjacquin in #64

New Contributors

• @radwo made their first contribution in #61

Full Changelog: v1.3.1...v1.3.2

v1.3.1

Fixed

• Allow ipv4 mapped to ipv6 (#56) #56 @josevalim
• Add items to array (#55) #55 @josevalim
• Ping is a regular message event (#54) #56 @josevalim

What's Changed

• Ping is a regular message event by @josevalim in #54
• Add items to array by @josevalim in #55
• Allow ipv4 mapped to ipv6 by @josevalim in #56
• Release v1.3.1 by @yjacquin in #57

New Contributors

• @josevalim made their first contribution in #54

Full Changelog: v1.3.0...v1.3.1

v1.3.0

Added

• Added automatic forwarding of query params from to the messages endpoint @yjacquin

Fixed

• Declare rack as an explicit dependency #49 @subelsky
• Fix notifications/initialized response #51 @yjacquin

What's Changed

• 🔧 Fix notifications/initialized response by @yjacquin in #51
• Declare rack as an explicit dependency, since RackTransport requires it by @subelsky in #49

New Contributors

• @subelsky made their first contribution in #49

Full Changelog: v1.2.0...v1.3.0

v1.2.0

Added

• Security enhancement: Bing only to localhost by default #44 @yjacquin
• Prevent AuthenticatedRackMiddleware from blocking other rails routes#35 @JulianPasquale
• Stop Forcing reconnections after 30 pings #42 @zoedsoupe

What's Changed

• 🔌 Don't force reconnections after 30 pings by @yjacquin in #42
• 🛡️ Security: Prevent connecting from outside localhost by default by @yjacquin in #44
• Add check against Rails env for localhost_only binding by @yjacquin in #45
• Fix authenticated rack middleware by @JulianPasquale in #35

New Contributors

• @JulianPasquale made their first contribution in #35

Full Changelog: v1.1.0...v1.2.0

v1.1.0

Added

• Security enhancement: Added DNS rebinding protection by validating Origin headers #32 @yjacquin
• Added configuration options for allowed origins in rack middleware #32 @yjacquin
• Allow to change the SSE and Messages route #23 @pedrofurtado
• Fix invalid return value when processing notifications/initialized request #31 @abMatGit

What's Changed

• Bump softprops/action-gh-release from 1 to 2 by @dependabot in #20
• feat: Allow to change the SSE and Messages route by @pedrofurtado in #23
• Fix #30 by wrapping nil response with send_response method by @abMatGit in #31
• Yorick/prevent dns rebinding attacks by @yjacquin in #32
• Release 1.1.0 by @yjacquin in #33

New Contributors

• @dependabot made their first contribution in #20
• @pedrofurtado made their first contribution in #23
• @abMatGit made their first contribution in #31

Full Changelog: v1.0.0...v1.1.0

v1.0.0

Added

• Rails integration improvements via enhanced Railtie support
• Automatic tool and resource registration in Rails applications
• Extended Rails autoload paths for tools and resources directories
• Sample generator templates for resources and tools
• MCP Client configuration documentation as reported by #8 @sivag-csod
• Example Ruby on Rails app in the documentation
• FastMcp.server now exposes the MCP server to apps that may need it to access resources
• Automated Github Releases through Github Workflow

Fixed

• Fixed bug with Rack middlewares not being initialized properly.
• Fixed bug with STDIO logging preventing a proper connection with clients # 11 @cs3b
• Fixed Rails SSE streaming detection and handling
• Improved error handling in client reconnection scenarios
• Namespace consistency correction (FastMCP -> FastMcp) throughout the codebase

Improved

• ⚠️ [Breaking] Resource content declaration changes
  • Now resources implement content over default_content
  • content is dynamically called when calling a resource, this implies we can declare dynamic resource contents like:

  class HighestScoringUsersResource < FastMcp::Resource
  ...
    def content
      User.order(score: :desc).last(5).map(&:as_json)
    end
  end

• More robust SSE connection lifecycle management
• Optimized test suite with faster execution times
• Better logging for debugging connection issues
• Documentation had outdated examples

What's Changed

• Update README.md by @dvantuyl in #12
• v1.0.0 Release by @yjacquin in #15

New Contributors

• @dvantuyl made their first contribution in #12

Full Changelog: v0.1.0...v1.0.0

v0.1.0

[0.1.0] - 2025-03-12

Added

• Initial release of the Fast MCP library
• FastMcp::Tool class with multiple definition styles
• FastMcp::Server class with STDIO transport and HTTP / SSE transport
• Rack Integration with authenticated and standard middleware options
• Resource management with subscription capabilities
• Binary resource support
• Examples with STDIO Transport, HTTP & SSE, Rack app
• Initialize lifecycle with capabilities
• Comprehensive test suite with RSpec